Self-employed people work an average of 55 hours a week, 13 hours more than those who have a full-time job with a company, according to a survey by the ING financial services group.

The study of 900 entepeneurs also found that the self-employed take less holidays and many lie awake at night worrying about their business. One in five of those questioned said they find it difficult to separate their work from their private life.